Sulphur-containing terpenes and method of producing



Patented Apr. 13, 1937 UNITED STATES SULPHUR-CONTAINING TERPENES AND METHOD OF PRODUCING Joseph N. Borglin, Wilmington, and Emil on, Elsmere, Del., assignors to Hercules Powder Company, Wilmington, Del., a corporation of Delaware No Drawing. Application April 11, 1935, Serial No. 15,854

26 Claims.

This invention relates to methods for the production of terpene mercaptans and sulphides.

In accordance with this-invention, it has been found possibleto effect a reaction between unsaturated terpene'compounds and hydrogen sulphide resulting in the formation of terpene mer captans and sulphidea The reaction in accordance with this invention. involves the addition of hydrogen sulphide at, the unsaturated bonds of the terpene compound with the resultant formation, according to the conditions of reaction, of mercaptans or sulphides, Mono-mercaptans will be formed by simple com- Y bination between one molecule of hydrogen sulcompound, while by the .interaction of several molecules of each reactant'or by the reaction of the mercaptans first.formed with itself or with' the unsaturated terpene compound present, va-'- rious sulphides or thioethers may be formed.- In the presence of any oxidizing agent, as, for example, air, the mercaptans will also be converted into dior polysulphides. The addition of hydrogen sulphide to more than one double bond will result in the formation of poly-merca'ptans.

The unsaturatedterpene compounds, which may be, for example, pinene, dipentene, terpinene, terpinolene, terpineol, 'etc., or mixtures, or polymers thereof, will be treated with hydrogen 30 sulphideunder suitable conditions. The terpene compound may be dissolved in a non-reactive solvent, as for example, benzene, toluene, butanol, gasoline; etc., or, if liquid at the temperature em-- ployed, may be used without a solvent. Hydrogen sulphide will then be passed through the liquid or solution until the reaction issubstantially completed, for example, for a period varying from 6 to 72 hours depending upon the conditions of reaction. The use of any particular temperature 40 is not essential to the reaction, but too low a temperature will decrease the rate of reaction unduly, while too high a temperature will tend to cause decomposition of the reaction product. A temperature range of from about 0 C. to about 300 C. is suitable for the reaction, although a range of from about 40 C. to 200 C. is preferred. The reaction will progress at any pressure, but the use of superatmospheric pressure is preferred because of the increased rate of reaction and yield of product so obtained. The pressure may accordingly vary from about atmospheric to about 100 atmosphereaalthough these limits are.

in no way critical. I

The -terpene compounds need not be in the ,form of pure compounds in order to be treated in accordance with this invention for-the production of mercaptans and sulphides, but may be reacted in a crude form. Thus, in place of the .several pure terpene compounds, crude natural 60 mixtures of terpene compounds, as for example,

phide and one molecule of unsaturated terpeneturpentine, pine oil, etc. may be used. 0r various fractions'distilled from these mixtures may be used without the necessity of isolating the several terpene compounds in their pure state. The color of the terpene mercaptans and/or sulphides produced will be made lighter, by giving the terpene compound to be treated an aqueous caustic wash or by steam distilling itin the presence of alkali before mercaptanization.

In particular, certain terpene-containing mixtures which are of little commercial value may advantageously be treated with hydrogen sulphide in accordance with this invention with the production of valuablepro'ducts.

In various stages of procedure for the production of turpentine and pine oil by the so-called steam and solvent process, fractions or cuts are,

obtained, which, although they may contain relatively large quantities of valuable .terpenes, are commercially worthless because the presence of undesired constituents renders them unsalable. The various constituents of these cuts, valuable and undesirable, have boiling points and solubilities that render their separation by fractional distillation impossible as a practical matter.

Thus, for example, the usual steam and solvent process involves the steam distillation oi? chipped pine wood for the removal of most of the turpentine and pine oil, followed by the extraction of the steamed chips with, for example, a petroleum fraction similar to gasoline and having a boiling range of 120-160 C. This removes the residual turpentine and pine oil and also rosin. The mixture of turpentine and pine oil obtained by the steam distillation is fractionated into a plurality of cuts. The lowest boiling cut is largely 'alpha-pinene and is sold as wood turpentine. The next cut is usually termed the para-menthane out, and contains a rather large quantity of this material, which is objectionable in turpentine. 'This out also contains considerable Also, when the gasoline solution of turpentine,

pine oil and rosin, obtained by extraction of ,the steamed pine chips, is subjected to fractionation, a plurality of cuts are obtained. These cuts comprise gasoline, a gasoline-terpene mixture, and. pine ,oil, rosin being left as a residue. The gaso-v lineterpene mixture contains valuable terpens, chiefly alpha-pinene,' together with some dipentene, and beta-pinene, but these terpenes cannot be recovered by fractional distillation and the presence of gasoline renders the cut as a whole of slight value.

When, for example, the terpene mixture constituting the paramenthane cut, described above, is treated in accordance with this invention with hydrogen sulphide, the unsaturated terpenes, suchas, dipentene, pinene, etc. present will react with the hydrogen sulphide to form mercaptans or sulphides. The saturated terpenes pres cut, as, for example, para-menthane, will, however, not react, and may readily be removed from the reaction product by distillation or the like.

Similarly, the gasoline-terpene mixture described above may be treated with hydrogen sul-. phide, which will react with the terpenes present but will not react to any substantial extent with the gasoline. The gasoline may accordingly be removed from the reaction product by, for exphoric acid and silica gel, is often more eflective than single catalysts. Desirably, acids will be used as catalysts in the reaction according to this invention, preferably in conjunction with a contact catalyst such as, for example, activated charcoal, silica gel, etc.

The catalyst will desirably be used in an amount about five times that of the terpene compound, although more or less can be used if desired. Smaller amounts of catalysts than this will tend to reduce the rate and yield, while larger amounts will not substantially increase either the rate or yield.

The mineral acid catalysts will desirably be .employed in concentrations of from 5 to For example, sulphuric acid in concentration of 5 to 90% is efiective, and phosphoric acid may be used in concentration of from 10 to 98%. When using the mineral acids as a catalyst it is advisable to add the catalyst in portions from time to time during. the progress of the reaction rather than all at onceat the start of the reaction. These acid catalysts lose much of their activity after having once been used in the reaction, but the activity may be restored by adding a small amount of anhydrous or concentrated acid to the spent acid. Reactivation can also be accomplished by heating the spent acid catalyst to about 80 C.-'C. for about an hour, cooling, and filtering through activated charcoal.

If it is desired to produce terpene mercaptans unmixed with terpene polysulphides, it is desirable to exclude air from the reaction mass in order to avoid oxidation of the mercaptans asterpene polysulphides, the terpene mercaptans maybe oxidized to polysulphides as they are formed by introducing air or oxygen to the reaction zone along with the hydrogen sulphide or independently.

It will be understood accordingly that all examples given for the production of terpene mercaptans will serve likewise for the production of the corresponding terpene polysulphides, it be- 1 30 parts by volume of sulphate pinene' and 150 parts by volume of phosphoric acid (85%) were contacted with hydrogen sulphide at atmospheric pressure during eighteen hours, with agitation' at about 22 C. The temperature rose to about 40 C. during the first few hours. Shortly after stopping the agitator, the product separated into layers. The upper layer comprising the treated pinene was drawn oif and water washed. The product analyzed 12.8% sulphur, equivalent to a 68% yield of mercaptan.

Example I! To illustrate the added eflect of contact catalysts, the above experiment was repeated using 1 part by weight of activated carbon in conjunction with the other reactants. Time, temperature, .and pressure were the same in each case. The resulting product after water washing analyzed 17.7% sulphur, representing a 94.3% yield of mercaptan.

Example III 30 parts by volume of pinene were contacted with parts by volume of 32% sulphuric acid and Has during twenty-four hours at room temperature and atmospheric pressure. The temperature rose to about 40 C. The water washed product analyzed 15.6% sulphur, indicating an 83% yield of mercaptans.

Sulphuric acid like phosphoric acid can be used in conjunction with absorbents such as activated carbon, silica gel, etc.

Example IV 30cc. of dipentene and 125 cc. of 85% phosphoric acid were contacted with hydrogen sulphide during twenty-four hours at atmospheric pressure. The temperature, rose to about 40 C. during the first few hours of the reaction. The separated product was water washed and analyzed as follows:

, Percent Sulphur 9.1 Mercaptans 47.8

Example V 10 cc. of terpineol and 50 cc. of 85% phosphoric acid were contacted with hydrogen sulphide, at atmospheric pressure, durin twenty-four hours.

The temperature rose to about 40 C. during the first ;few hours of the reaction. The product was drawnofi and water washed. It analyzed as follows:

v Percent Sulphur 10.4

Mercaptansnna 61 Example VI i parts by volume of pinene and 50 parts by volume of monoamylamine were contacted with HzS during twenty-four hours at about 5-10# gaugepressure and 80 C. The product was diluted with a small quantity of water to cause 15 separation; the resulting upper oily layer was again water washed to remove all traces of the catalysts. The resulting product analyzed, sulphur 2.8%, equivalent to a 15.8% yield of mercaptans.

Emmpze VII 10 parts by volume of turpentine, 10 parts by weight of slacked lime and parts by weight of waterwere contacted with H during 60 hours 25 at 22 C. The temperature rose to about C. during the 'flrst few hours of the reaction. The treated-turpentine was then water-washed-and the resulting product analyzed 3.6% S and gave a positive test for mercaptans.

Example VIII 10 parts by volume of turpentine and 40 parts by volume of 90% acetic acid were contacted with H2S at 22 C. during forty-eight hours. The tem- 5 perature rose to about 40 C. during the first few hours of the reaction. The water-washed product analyzed 12.7% S and gave a positive test for mercaptans.

Example IX 10 parts by volume of turpentine and 40 parts by volume of 32% H2804 were contacted with H28 at 22 C., and during 48 hours. The tem perature rose to about 40 C. during the first few hours of the reaction. The water-rwashed product analyzed 16% S and gave a positive test for mercaptans.

' Example X I The previous experiment was repeated at 80 C.

50 in place of 22 C. The water-washed product gavea positive test for mercaptans and analyzed 25.4% S.

' Example XI 10 parts by volume of turpentine and 20 parts by weight of P205 (the latter preferably added A slowly and with cooling it necessary) were con- I tacted with I-hS', at 22 .C. during sixty hours;

The temperature rose to about 40 C. during the first'tew hours of the reaction. The waterwashed product gave a positive test tor mercaptans and analyzed 14.9% S. This sulphur content is equivalent to an 84.2% yield in terms 0! mercaptans..

7 Example x11 I" .10 parts by volume of turpentine and 40-parts by volume of 32% H2804 were contacted twenty- -Iour hours with ms at C. The resulting 0 water-washed product analyzed 17.35% s and gave a'posltlvetest for mercaptans. I Emmple xll l i The above experiment was'repeated using 75 H1104 in place of 32% The waterwashed product contained much water in suspension and required heating to remove the water by distillation. The resulting product analyzed 10.5% S and gave a positive test for mercaptans. In all the examples the mercaptan content is that calculated from the sulphur content on the assumption that no side reactions took place. I ExampleXIV Potassium hydroxide as a catalyst appears to cause the formation of sulphides or disulphides to the exclusion of mercaptans. Thus, 10 parts by volume of turpentine and 40 parts by volume of 40% KOH in alcohol were contacted with 1 H23, at 22 C., during a period of twenty-four hours. The product was water-washed. The resulting product analyzed 12.4% S. However, it

gave a negative test for mercaptans.

The crude products as prepared in the above examples will comprise both terpene mercaptans and/or sulphides and the unreacted portion of the .terpenecompound used in the reaction. Simple fractionation, extraction, etc. will remove the'unreacted terpenes, and produce the mercaptans or sulphides in high concentration and in a. substantially pure state.

The following examples illustrate treatment of the so-called paramenthane out and of a gasoline-terpene mixture in accordance with this invention: y,

Example XV 500 cc. of a gasoline-terpene mixture, as described above, -500 cc. of 85% phosphoric acid, and 6 g. of activated carbon were contacted with hydrogen sulphide at 20 C. and at a. gauge pressure of 200-300 lbs. sq. in. for seven hours.

The'original gasoline-terpene mixture analyzed as follows:

The product, after treatment as al'ove with hy- This drogen sulphide analyzed 13.22% sulphur. product was then fractionated at atmospheric pressure through a three plate column with the following results:

. Analysis Vapor Percent 0! Fraction No. temperaorlgiual l turo volume Unpol. Sul- R I residue phur Percent Percent, 135-1 10 1 73. 5 0. 4 l. 4362 149:151 5 70. 0 4 1. 4372 151-159 '10 .62.7 .4 1.4423 159-160 5 56.0 .6 1.4483 -166 j 10 40.5 .9 1.4577 6 166477- 10 20.0 3.0 1.4723 Residue Above 177 50 0.7 20.2 1.5170 3 The residue constitutes substantially pure ter-J pane mercaptans. and sulphides.

Example XVI 500 cc. of paramenthane cut, as described above, 500 cc. of 85% phosphoric acid, and 6 g. of activated carbon were contacted with hydrogen sulphide at 20 C. and 200 300 lbs. sq. in. pressure for seven hours.

The original paramenthane cut analyzed as follows:

The paramenthane cut, after treatment as 25 above, analyzed 14.33% sulphur. This product was then fractionated through a three plate column at atmospheric pressure as above, with the following results:

30 Analysis Vapor Percent of Fraction No. temperaoriginal ture volume Unpol. Sul- R I residue phur 0. Percent Percent 155-162 5 42. 0. 2 1. 4561 162-164 5 39. 5 7 1. 4581 164-166 5 38. 5 .0 1. 4500 166-168 5 38. U l. 3 1.4602 168-169 5 34. 1. 7 1.4628 169-172 24. 6 2. 7 l. 4695 172-177 5 l4. 7 4. 6 1. 4782 177-203 5 7. 1 8. 7 l. 4852 Above 203 60 2 20. 8 1. 5140 The residue from the above fractionation had the following A. S. T. M. boiling range:

10 221.5 224.5 -227.o --231.5 50 ---234.5 -z3a.o '10 -24a.o so --247.o

- 9o 251.o 95 --26'l.5

and consisted of substantially pure terpene mercaptans and sulphides.

The terpene mercaptans and sulphides in ac- (m cordance with this invention may be used as flotation agents in the flotation refining of ores, or they may be used as raw materials for the production of the corresponding sulphonic acids, trithiocarbonates, etc., which are of value as wetting out agents, flotation agents, organic intermediates, etc;

This application is filed as, and constitutes, a continuation input of our copending application Serial No. 713,304, filed February 28, 1934.

' What we claim and desire to protect by Letters Patent is:

1. The method of producing a sulphur-containing terpene compound which includes reacting 'an unsaturated terpene A compound with hydrogen 7 sulphide in the presence of a catalyst selected from the group consisting of acidic catalysts. basic catalysts, contact catalysts, dimethyl sulphate, metallic aluminum and metal sulphides.

2. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hy drogen sulphide at a temperature adapted to promote the reaction.

3. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide at a temperature adapted to promote the reaction and in the presence of a catalyst selected from the group consisting of acidic catalysts, basic catalysts, contact catalysts, dimethyl sulphate, metallic aluminum and metal sulphides.

4. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide under pressure.

5. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide at a temperature of from about 0 C. to about 300 C.

6. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide in the presence of an acid.

7. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide in the presence of an acid anhydride.

8. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide at a temperature adapted to promote the reaction and in the presence of an acid.

9. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide at a temperature adapted to promote the reaction and in the presence of an acid anhydride.

10. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide.

-11. The reaction product of an unsaturated terpene compound and hydrogen sulphide.

12. The reaction product of pinene and hydrogen sulphide.

13. The method of producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide in the presence of a base.

14. The method of producing a terpene mercaptan which includes reacting an unsaturated terpene compound with hydrogen sulphide in the absence of oxygen. 4

15. The method of producing a terpene sulphide which includes reacting an unsaturated terpene compound with hydrogen sulphide in the presence of oxygen.

16. The method of producing a sulphur-containing terpene compound which includes treating a mixture comprising an unsaturated terpene compound and gasoline with hydrogen sul-. phide at a temperature adapted to promote re action between the hydrogen sulphide and the unsaturated terpene compound and separating sulphur-containing terpene compound in substantially pure form from the resultant mixture.

antenna reacted materials and recovering sulphur-containing terpene compound in substantially pure form. 4

18. The method of producing avsulphur-contaming terpene compound which includes treating a mixture comprising an. unsaturated terpene compound and a saturated terpene compound with hydrogensulphide at a temperature adapted to promote reaction between the hydrogen sulphide and the unsaturated terpcne compound -and separating sulphur-containing terpene compound in substantially pure form from the resultant mixture.

19; The method of producing a sulphur-containing terpene compound which includes treating a mixture comprising an unsaturated terpene compound and a saturated terpene compound with hydrogen sulphide at a temperature adapted to promote reaction between the hydrogen sulphide and the unsaturated terpene compound, distilling ofi unreacted materials and recovering sulphur-containing terpene compound in substantially pure to.

20. Thereaction product of dipentene and hydrogen sulphide.

21. The rwction product of terpineol and 11 7- drogen sulphide.

22. The method oi producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hydrogen sulphide in the presence of phosphoric acid.

23. The method of producing a sulphur-containing terpene compound which'includes reacting an unsaturated t'erpene compound with bydrcgen sulphide in the presence of an amine.

"24. The method oi producing a sulphur-containing terpene compound which includes reacting an unsaturated terpene compound with hy drogen sulphide in the presence'of a mixed catalyst comprising a contact catalyst and a catalyst selected from the group consisting of acidic catalysts and basic catalysts.

25. The method of producing a sulphur-contaming terpene compound which includes reacting an unsaturated terpene compound in solution in-a solvent therefor with hydrogen sulphide.

26.. A terpene mercaptan.

unseen N. BORGLIN. mm. 

